In just the second Major League start for Arizona's No. 4 prospect (according to MLB Pipeline), Banda went six innings, giving up one run on three infield hits as the D-backs remained a half-game ahead of the Rockies for the top National League Wild Card spot.
"I thought he did a really good job," manager Torey Lovullo said. "He won his first Major League game, so you can't ask for more."
The only damage the Giants did against the left-hander came in the fourth, when they loaded the bases with one out on a bunt single, a walk and an infield single off Banda's glove. Banda walked Brandon Crawford to bring in a run, and it looked like the inning might have been getting away from him. But Banda struck out Gorkys Hernandez and got Ryder Jones to ground out to end the inning.
"I was just getting way too ahead of myself," Banda said. "I was trying to press instead of just trusting my stuff and staying down in the zone for quality. That's when I told myself, 'You know what, they're human beings, too.'
"So I went right after them, stayed down in the zone and trusted my guys behind me and behind the plate. It was a confidence booster, getting out of that inning with minimal damage and getting back and doing what I did."
D-backs first baseman Paul Goldschmidt, who knocked in both runs to support Banda, added, "It could be easy to give in right there and give up another run, but he was able to get out of that inning and give us a chance to win with only scoring two runs, which is tough to do."
Banda then recovered with a vengeance in the fifth, striking out the side on 16 pitches. He got both Denard Span and Kelby Tomlinson looking on pitches low in the zone.
He started the sixth inning by hitting Giants first baseman Brandon Belt in the head with a curveball, something Banda was remorseful for in the moment and after the game. Lovullo was impressed that Banda was able to settle down and work out of the inning.
"That's a very unfortunate situation. A breaking ball gets away from him and hits [Belt] in the head," Lovullo said. "You're wanting to make sure things get solidified and stay under control, and he did a great job and deserves a lot of credit."
And, through two starts with the big league team, Lovullo is impressed with what he's seen from the 23-year-old.
"He's mature beyond his years and he did a great job," Lovullo said.
Alex Simon is a reporter for MLB.com and covered the D-backs on Friday. Follow him on Twitter at @alexsimon99.